Well, i'm not sure how many cornell people are still around on the boards, but if you do a search you should find some good responses from the previous years. I'm a current MS2, so i'll give you some of my opinions, in brief:
Student life: really good!! You have a decent amount of time during the first semester to really enjoy the city, and even after that, since everything is so close, lots of people regularly go out and do stuff. We even have some outdoorsy types (myself included) that although are a bit stymied by lack of nearby skiing, etc., still have ice skating rinks, central park, etc., to enjoy. Lot of museums, theaters, and so on - obviously, because it's NYC. Also, we're located in a very safe neighborhood, so you can go out pretty much whenever.
Professors: can be good or bad, depending on the class. Overall, our anatomy/physiology course and neuro courses are outstanding - i really do think we have some of the best profs in those departments. It doesn't really matter though, because every school has good/bad profs; we get full transcripts and slides for every lecture (they're also online), so you can really learn the material just that way if you wanted. Or use the review books.
Classes: again, good and bad. First year, we have three main 'modules'; the first is biochem/genetics, etc.; the second is anatomy/physiology, and the last one is micro/immuno. The first one is kind of sucky, but the second two are great. Second year we have two courses, neuro/psych, which is absolutely outstanding, and pathology, which is pretty good so far (we're only in the third week). You can get all of the details from the website, so i'd say read that and then post if you have specific questions.
By the way - Cornell is very strong in international medicine; we have a very active student organization, about 16/100 people went abroad during the first summer (we get $$ from the school to go!) and we sponsor a lot of international research, electives, etc. So if you're into that, this is the place to come.
Q